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I'm building a motor driver circuit, and am looking at diodes to clamp the output voltage between the supply rails. Apparenly, I should use schottky diodes for this purpose.

My question is, are there ICs out there than contain a pair of diodes arranged as shown below?

┌───►|──┬──►|───┐
│       │       │
0V      S       V+

Or should I just buy a pair of single diodes?

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  • 1
    \$\begingroup\$ Why the downvote? It seems like a great question to me, sometimes just finding the right name or search terms is all thats needed to answer questions, doesn't make it a bad question though. \$\endgroup\$ – Kellenjb May 2 '11 at 14:37
  • \$\begingroup\$ Why do you need Schottky diodes? \$\endgroup\$ – starblue May 2 '11 at 18:58
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They're simply called "double Schottky diodes" :-). They often come in different configurations, like for instance the BAT54:

BAT54A: common anode
BAT54C: common cathode
BAT54S: in series, one diode's cathode connects to the other's anode
BAT54: is the single diode version

enter image description here

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  • \$\begingroup\$ Do these exist in 0.1" through-hole packages? \$\endgroup\$ – Eric May 2 '11 at 15:46
  • \$\begingroup\$ @Eric; see vishay.com/docs/94554/8sth06.pdf for a TO220 (0.1") package, as mentioned in my answer. Although such a device may be overkill with its 600V rating... \$\endgroup\$ – Thomas O May 2 '11 at 17:17
  • \$\begingroup\$ BAT54 is a very popular "default" schottky diode. Good for anything up to 50~100mA and 30V. It will survive up to 200mA. If you need more current, then you will likely end up with two separate power diodes instead. If you need higher switching speed and/or higher voltage, then you should look at BAS40 or BAS70. They are faster and can handle higher voltages, but much lower currents. \$\endgroup\$ – Timmy Brolin Nov 25 at 16:10
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Yes, such devices do exist; they are known as dual Schottky or dual diodes.

The most common arrangement is two diodes with a common cathode; these are used in switch mode power supplies to boost the allowable current from a typical single diode in package.

However, dual series diodes do exist; here is one example of a power device: VS-8STH06FP.

Another example of a device not intended for high power applications is BAV99W, which is a very popular device.

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